Lamp



June 12, 1928.

1,673,100 F. BUCHANAN ET AL LAMP Filed Jan. 1928 v INVENTORS @Mfldffl/M A TTORNE Y5 Patented June 12, 1928.

UNITED STATES PA ENT OFFICE.

FRAN'K BUCHANAN AND 'KENNETH W. MACKALL, OE SYRACUSE, NEW YORK, AS SIGNORS TO CROUSE-HINDS COMPANY, OF SYRACUSE, NEW YORK, A CORPORATION OF NEW YORK.

Application filed January 6, 1928.

This invention relates to lamps such as are used for flood lights and has for its object,

a lamp provided with a relative arrangement of the reflector and a source of light whereby the light is projected laterally through an arc of substantially 180 and, more particularly a lamp for illuminating air ports or aeroplane fields or any place where wide, even and bright illumination is required.

The invention consists in the novel features and in the combination and constructions hereinafter set forth and claimed.

In describing this invention, reference is had to the accompanying drawings, in which like characters designate corresponding parts in all the views.

Figure l is an elevation of a lamp embodying our invention.

Figure 2 is a vertical sectional view there through.

Figure 3 is a transverse sectional view looking downwardly.

The lamp or lighting unit comprises generally, a body having a reflector parabolic and semi-circular in any sections taken at right angles to each other with the souce of light arranged in the intersection of the axes, of the parabolic curve and the axis of revolution.

The lamp is usually arranged in vertical position.

Preferably, the lamp is in the form of a globe parabolic in vertical section and circular in cross section, one-half of the globe on one side of a plane containing the axis of revolution of the parabolic curve, being mirrored to form a reflector and the other or front half of the globe being transparent. The forward or transparent half, however, may not necessarily be parabolic and semicircular but is preferably so in order that it may be normal to the rays of light projected from the reflector.

1 designates the body which is preferably formed of glass so that it is practically a globe, one-half of the reflector being silver-ed or otherwise mirrored as indicated at M to form a reflector, this half being located on the rear side of a plane containing the axis A of the body.

3 designates the transparent front half.

S designates the source of light which is arranged substantially at the point of inter- LAMP,

Serial No. 244,856.

section I of the axis of the parabolic curve A and the axis of revolution A. The source of light is the filament of an ordinary incandescent bulb 5 suitably supported in a socket 6 carried by a base 7 and this base may be suspended. The body 1 is carried by the base in any suitable manner and the body is here shown as open at its lower end for permitting the insertion of the lamp or permitting the globe to be removed from the base and the lamp is held in position by tie-rods 8 extending through a cap 9 lying on the upper end of the body and through a flange 10 on the base, the upper end of the body being flattened in order to receive the cap.

The body is usually formed with length wise diametrically opposite ribs 11 at the junction of the front and rear halves of the body or globe and with small projections or rounded points 12 on opposite sides of the globe and in alignment with the intersection of the axes of the parabolic curve and revolution midway between the ribs 11. These ribs and points serve as gages or sights for locating the bulb with its filament at or close to the focus of the reflector, it being understood that the bulb is adjustable in any of the many well known ways.

In operation, the rays of light striking the reflecting surface or mirror will be projected horizontally forwardly due to the parabolic curve of the reflector and laterally through a range of 180 due to the transverse circula'r curve of the reflector.

As the source of light is arranged as accurately as possible in the focus of the parabolic circular curve, the light will have a general horizontal projection through an arc of 180.

What We claim is:

In a device of the character described, a support, a source of light carried by said support, a globe on said support surrounding said source of light, a cap engaging said globe, means operating through said cap for forcing the lobe into engagement with said support, said globe being formed by revolving a vertical parabolic are about a line passing through the focus and at right boliccurve and the axis of revolution, the. i said ribs and projections serving as gauges whereby the light source may be properly located with respect to the focus of the re- 10 fleeting surface.

In testimony whereof, we have hereunto signed our names at Syracuse, in the county of Onondaga and State of New York, this 14th day of Dec., 1927.

FRANK BUCHANAN. KENNETH W. MACKALL. 

